Fluoroprobe - Tagged Polysaccharide Vesicles for Drug Delivery Application

Abstract

Polysaccharide derived nano-carriers are emerging in drug/gene delivery area to cancer cells and are drawing a lot of attention. One of the major reason is the biocompatibility of these polysaccharides which is a very essential factor while designing a carrier for such biomedical applications. Design and synthesis of a fluorescent dextran nano-carrier for the delivery of the Cisplatin drug to the cancer cells has been shown in this report. The fluorescent tag on the polymer scaffold enables the tracking of the Cisplatin drug, which is otherwise difficult, given the non-fluorescent nature of the drug. Thus the system provides an insight in the fate of the polymer as well as the drug, giving us a twofold information. The fluorophore used in the system shows an Aggregation Induced Emission (AIE). Moreover, it makes an excellent FRET pair with Rhodamine – B dye. Knowing this, a fluorescent polymer with a tetraphenylethylene (TPE) chromophore substitution was made by first synthesising an acid derivative of the TPE molecule along with a substitution of a pentadecylphenol (PDP) unit to maintain the amphiphilicity of the polymer. An acid handle was incorporated to enable chemical conjugation of the Cisplatin drug. Further, this polymer was charecterized by 1H and 13C NMR spectroscopy and IR spectroscopy. Drug conjugation and dye loading studies were done. The size of the nanoparticle was charecterised using Dynamic Light Scattering (DLS). An enzyme degradation study was done to check the release kinetics and biodegradability. Further, an MTT assay was done to check the cytotoxicity of the polymers and cell killing in the cisplatin stitched counterpart